aquatic_ws: mio: replace native_tls with rustls, rewrite connection state logic completely (#38)

* ws: mio: use rustls, rewrite Connection logic

* ws: mio: improve poll register/deregister handling

* ws: mio: work on type-level poll registry safety

* ws: mio: use stronger poll registry type-level guarantees

* ws: mio: fix stream reading

* ws: clean up, run fmt

* ws: mio: don't require registered connection for writing, improve docs

* ws: mio: add Connection::get_meta(), make Connection::meta private

* ws: mio: add ConnectionMap struct; remove utils.rs

* ws: mio: move token counter into ConnectionMap, improve docs

* ws: mio: connection: move Connection struct above state structs

* Update TODO

* ws: fix build errors

* ws: upgrade to tungstenite 0.16

* ws load test: don't panic on Close message; print shorter errors

* ws: fix socket worker bugs, add log statements

* ws: mio: wait for write availability if would block for ws messages

* Update README

* ws: mio: limit channels & queues; read 1 message only; other fixes

* ws: mio: send local responses each event; decrease channel size

* Update TODO

* ws: mio: limit ws send queue, fixing memory leak; limit pending messages

Also change some log output levels and run rustfmt

* Update TODO

* Update TODO

aquatic_ws/src/common/mod.rs

@@ -1,5 +1,7 @@
 pub mod handlers;
 
+use std::fs::File;
+use std::io::BufReader;
 use std::net::{IpAddr, SocketAddr};
 use std::sync::Arc;
 use std::time::Instant;
@@ -142,3 +144,32 @@ impl TorrentMaps {
         torrent_map.shrink_to_fit();
     }
 }
+
+pub fn create_tls_config(config: &Config) -> anyhow::Result<rustls::ServerConfig> {
+    let certs = {
+        let f = File::open(&config.network.tls_certificate_path)?;
+        let mut f = BufReader::new(f);
+
+        rustls_pemfile::certs(&mut f)?
+            .into_iter()
+            .map(|bytes| rustls::Certificate(bytes))
+            .collect()
+    };
+
+    let private_key = {
+        let f = File::open(&config.network.tls_private_key_path)?;
+        let mut f = BufReader::new(f);
+
+        rustls_pemfile::pkcs8_private_keys(&mut f)?
+            .first()
+            .map(|bytes| rustls::PrivateKey(bytes.clone()))
+            .ok_or(anyhow::anyhow!("No private keys in file"))?
+    };
+
+    let tls_config = rustls::ServerConfig::builder()
+        .with_safe_defaults()
+        .with_no_client_auth()
+        .with_single_cert(certs, private_key)?;
+
+    Ok(tls_config)
+}